1. Field
The following description relates to a rechargeable battery, and more particularly, to a rechargeable battery having current collecting plates with improved structural characteristics.
2. Description of the Related Art
A rechargeable battery differs from a primary battery in that it can be repeatedly charged and discharged, while the latter generally irreversibly converts chemical energy to electrical energy. A low-capacity rechargeable battery is used as a power supply for small electronic devices, such as cellular phones, notebook computers, and camcorders, while a high-capacity rechargeable battery is used as a power supply for driving motors, for instance, in hybrid vehicles and the like.
A high-power rechargeable battery using a non-aqueous electrolyte with high energy density has been recently developed. For example, the high-power rechargeable battery is constructed with a high-capacity rechargeable battery having a plurality of rechargeable cells coupled to each other in series such that it can be used as a power supply for driving motors in electric vehicles requiring high power.
One high-capacity rechargeable battery is commonly formed with a plurality of rechargeable cells coupled to each other in series. The rechargeable battery may have a cylindrical shape or a prismatic shape.
The prismatic rechargeable battery includes an electrode assembly with positive and negative electrodes and a separator interposed between the two electrodes, a case mounting the electrode assembly therein, a cap plate fitted to the case to seal it and having terminal holes, and terminals inserted into the terminal holes of the cap plate, the terminals protruding out of the case.
With a conventional prismatic rechargeable battery, lead tabs for electrically interconnecting the electrode assembly and the terminals are fixed to the lateral sides of the uncoated regions through ultrasonic welding. However, in order to weld the lead tabs to the lateral sides of the uncoated regions, the uncoated region has a greater length, needlessly enlarging the volume of the electrode assembly.
Furthermore, as the ultrasonic welding is performed on the uncoated regions through the lead tabs, the lead tabs should be thin. However, as the lead tabs are reduced in thickness, the resistance of the lead tabs is increased, and so heat is generated, and the output power is decreased.
Furthermore, if the rechargeable battery is impacted, a contact failure may occur between the lead tabs and the electrode assembly such that heat is internally generated, decreasing the output power.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art already known in this country to a person of ordinary skill in the art.